This invention relates in general to measuring devices and, in particular, to tape-type, linear measuring devices. More specifically, but without restriction to the particular use which is shown and described, this invention relates to an improved tape measuring device with two tapes adapted for measuring the linear distance between two points from any point therebetween, and registering the combined distance between the distal ends of the tapes on a counter.
To measure the linear distance between two points with a single tape measuring device, it is necessary to secure the end of the tape at one end point while making the reading at the opposite end point. This is often inconvenient, and sometimes impossible, for example, when measuring the distance between a floor and ceiling.
Another problem frequently encountered is measuring the total linear distance of two divergent lengths, such as when calculating the perimeter of a window frame. In order to measure the divergent linear dimensions of a structure, such as a window frame, with a single tape measuring device, it would be necessary to make at least two separate measurements.
It is, therefore, desirable to measure the distance between two points while locating the measuring device at any point therebetween. Also, it is desirable to measure the sum of two distances, such as the vertical and horizontal dimensions of a window frame, while locating the measuring device at the intersection of the two linear dimensions.
The prior art has attempted to solve these problems by utilizing measuring devices with two or more tapes in a single housing. One such device is disclosed in the A. Bouchard, U.S. Pat. No. 2,240,753. This device uses two simultaneously actuated measuring tapes enclosed in a single housing. By extending either tape, the other tape is simultaneously extended by a common set of gears from the opposite side of the housing the same distance. While somewhat beneficial over a single tape measuring device, because both tapes extend an identical distance, the Bouchard prior art device only measures from a point exactly central to the two linear end points. While this device may be suitable to mark off a set distance, it is not convenient for measuring an unknown distance since the exact center is not known, requiring movement of the housing until it is positioned exactly in the center of the unknown distance.
Another two-tape measuring device is disclosed in A. J. Banas, U.S. Pat. No. 3,885,314. This prior art discloses two tape measures in separate compartments of a single housing, allowing measurements to be taken in opposed directions. Since both tapes work independently of each other, the total linear distance can not be automatically determined. This device still requires two separate measurements to be taken, in a manner similar to using a single tape measuring device twice. This device contains no provision for determining the total distance between the ends of the tapes.
The present invention is adapted to solve the problems inherent in the prior art devices. This invention can be utilized to measure the total linear distance between two end points, using two tapes extending from opposite sides of a housing. When either tape is extended, the total distance between the tape ends is registered on a counter mounted in the housing. This allows a desired measurement to be taken anywhere between two end points, with the total distance between the two end points of the tape being shown on the counter.
In addition, this invention allows measurements to be taken simultaneously, which previously required two or more separate measurements. For example, one tape can measure the rise of a step, while the other tape measures the run. The total of both rise and run distances then is summed on the counter. This could be useful in making a measurement for carpeting stairs. A similar use could be in measuring the height and width of a window frame, with the number registering on the counter being one-half of the perimeter of the window frame, in determining board feet requirements.